If an AV receiver cannot process a streaming service's 7.1.4 mix, what often happens to the height objects?

Distinct height objects collapse into the nearest surround channels, diluting the intended effect

The flexibility of object-based audio relies heavily on the playback system possessing the processing power and physical outputs required by the incoming mix metadata. When a device, such as an AV receiver, receives a high-channel-count stream (e.g., 7.1.4) but lacks the necessary configuration or processing capabilities, it must perform a downmix. In this translation process, the positional data associated with the discrete height channels often cannot be accurately mapped or rendered to the limited number of available speakers. Consequently, the information intended for the overhead speakers is typically collapsed or merged into the nearest available channels on the main horizontal plane, which inherently dilutes or obscures the intended three-dimensional spatial separation.